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Grok-4 Fast Reasoning vs Muse Spark 1.3

Comparing Grok-4 Fast Reasoning and Muse Spark 1.3 across benchmarks, pricing, and capabilities.

xAI · Meta · Updated for 2026

Which is better?

Grok-4 Fast Reasoning and Muse Spark 1.3 trade strengths across price, capabilities, and technical limits. The better choice depends on the workload.

On price, Muse Spark 1.3 is roughly 2.2x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Grok-4 Fast Reasoning also accepts a larger context window (2,000,000 input tokens), making it the stronger choice for long documents and large codebases.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Grok-4 Fast Reasoning

  • you process long inputs — it offers a 2,000,000 token context window

Choose Muse Spark 1.3

  • cost matters — it's about 2.2x cheaper per token
  • you want the most recent training data — it shipped Sep 2026

At a glance

The differences that matter most.

Grok-4 Fast Reasoning
xAI
Muse Spark 1.3
Meta
Benchmark wins
—
—
Input price
$0.20 / M
$0.10 / M
Output price
$0.50 / M
$0.20 / M
Context window
2,000,000
1,048,576

Individual benchmarks

0 reported for Grok-4 Fast Reasoning · 11 for Muse Spark 1.3

No common benchmarks found

Grok-4 Fast Reasoning and Muse Spark 1.3don't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Muse Spark 1.3 costs less

For input processing, Grok-4 Fast Reasoning ($0.20/1M tokens) is 2.0x more expensive than Muse Spark 1.3 ($0.10/1M tokens).

For output processing, Grok-4 Fast Reasoning ($0.50/1M tokens) is 2.5x more expensive than Muse Spark 1.3 ($0.20/1M tokens).

In conclusion, Grok-4 Fast Reasoning is more expensive than Muse Spark 1.3.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Fri Sep 04 2026 • llm-stats.com
xAI
Grok-4 Fast Reasoning
Input tokens$0.20
Output tokens$0.50
Best providerxAI
Meta
Muse Spark 1.3
Input tokens$0.10
Output tokens$0.20
Best providerMeta
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Grok-4 Fast Reasoning accepts 2,000,000 input tokens compared to Muse Spark 1.3's 1,048,576 tokens. Muse Spark 1.3 can generate longer responses up to 943,718 tokens, while Grok-4 Fast Reasoning is limited to 30,000 tokens.

xAI
Grok-4 Fast Reasoning
Input2,000,000 tokens
Output30,000 tokens
Meta
Muse Spark 1.3
Input1,048,576 tokens
Output943,718 tokens
Fri Sep 04 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Grok-4 Fast Reasoning and Muse Spark 1.3 support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Grok-4 Fast Reasoning

Text
Images
Audio
Video

Muse Spark 1.3

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Grok-4 Fast Reasoning

Proprietary

Closed source

Muse Spark 1.3

Proprietary

Closed source

Release Timeline

When each model was launched

Grok-4 Fast Reasoning was released on 2025-08-28, while Muse Spark 1.3 was released on 2026-09-02.

Muse Spark 1.3 is 12 months newer than Grok-4 Fast Reasoning.

Grok-4 Fast Reasoning

Aug 28, 2025

1.0 years ago

Muse Spark 1.3

Sep 2, 2026

1 days ago

1.0yr newer

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Provider Availability

Grok-4 Fast Reasoning is available from xAI. Muse Spark 1.3 is available from Meta Model API.

Grok-4 Fast Reasoning

xai logo
xAI
Input Price:Input: $0.20/1MOutput Price:Output: $0.50/1M

Muse Spark 1.3

meta logo
Meta
Input Price:Input: $0.10/1MOutput Price:Output: $0.20/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Grok-4 Fast Reasoning and Muse Spark 1.3 side-by-side, then vote on the output you prefer.

Grok-4 Fast Reasoning
✓ Preferred
Muse Spark 1.3
Open in Playground

FAQ

Common questions about Grok-4 Fast Reasoning vs Muse Spark 1.3.

Which is better, Grok-4 Fast Reasoning or Muse Spark 1.3?

Grok-4 Fast Reasoning (xAI) and Muse Spark 1.3 (Meta) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

How does Grok-4 Fast Reasoning compare to Muse Spark 1.3 in benchmarks?

Muse Spark 1.3 scores MRCR v2 (8-needle): 98.5%, MRCR v2 (8-needle, 512K-1M): 98.1%, DeepSearchQA: 89.4%, Terminal-Bench 2.1: 88.8%, DeepSWE 1.1: 75.4%.

Is Grok-4 Fast Reasoning cheaper than Muse Spark 1.3?

Muse Spark 1.3 is 2.0x cheaper for input tokens. Grok-4 Fast Reasoning costs $0.20/M input and $0.50/M output via xai. Muse Spark 1.3 costs $0.10/M input and $0.20/M output via meta.

What are the context window sizes for Grok-4 Fast Reasoning and Muse Spark 1.3?

Grok-4 Fast Reasoning supports 2.0M tokens and Muse Spark 1.3 supports 1.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Grok-4 Fast Reasoning and Muse Spark 1.3?

Key differences include context window (2.0M vs 1.0M), input pricing ($0.20 vs $0.10/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Grok-4 Fast Reasoning and Muse Spark 1.3?

Grok-4 Fast Reasoning is developed by xAI and Muse Spark 1.3 is developed by Meta.

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